Merge branch 'ml/replace-auto-execok'

This addresses CVE-2025-46334, Git GUI malicious command injection on Windows. A malicious repository can ship versions of sh.exe or typical textconv filter programs such as astextplain. Due to the unfortunate design of Tcl on Windows, the search path when looking for an executable always includes the current directory. The mentioned programs are invoked when the user selects "Git Bash" or "Browse Files" from the menu. Signed-off-by: Johannes Sixt <j6t@kdbg.org>